The present invention relates to industrial process pressure transmitters that include pressure sensors that are isolated from industrial process fluids. More specifically, the present invention relates to sealing of isolation systems in such transmitters.
Industrial process control systems are used to monitor and control industrial processes used to produce or transfer fluids or the like. In such systems, it is typically important to measure “process variables” such as temperatures, pressures, flow rates, and others. Process control transmitters are used to measure such process variables and transmit information related to the measured process variable back to a central location such as a central control room.
One type of process variable transmitter is a pressure transmitter which measures pressure of a process fluid and provides an output related to the measured pressure. This output may be a pressure, a flow rate, a level of a process fluid, or other process variable. The transmitter is configured to transmit information related to the measured pressure back to a central control room or the like. The transmission is typically over a two wire process control loop, however, other process control loops may be used including those which use wireless technologies.
Pressure of the process fluid is coupled to a process fluid transmitter through some kind of a process coupling. For example, the process fluid can comprise a component used in an industrial process such as natural gas, oil, etc. Some of the materials may be under extremely high pressures. These high pressures can include cyclical pressure pulses that repeat over long period of times such as months or years, repeatedly cycling piping and other mechanical parts in contact with the process fluid.
There is a need to improve pressure transmitters to withstand repeated cyclical pressure pulses on high pressure process fluids over long periods of time.